The Most Dangerous Epidemics in U.S. History

A look back

As medicine advances, there are fewer infectious disease outbreaks, or epidemics. An epidemic is when an infectious disease spreads within a community or area during a specific time period. Learn about the biggest outbreaks to spread across the United States, and where we are now.

1633-1634: Smallpox from European settlers

Smallpox came to North America in the 1600s. People had symptoms of high fever, chills, severe back pain, and rashes. Starting from the Northeast, smallpox wiped out entire Native American tribes. Over 70 percent of the Native American population dropped. In 1721, 844 of the 5,889 Bostonians who had smallpox died from it.

End: In 1770, Edward Jenner developed a vaccine from cow pox. It helps the body become immune to smallpox without causing the disease.

Now: After a large vaccination initiative in 1972, smallpox is gone from the United States. In fact, vaccines are no longer necessary.

1793: Yellow fever from the Caribbean

Philadelphia was once the nation’s capital and its busiest port. One humid summer, refugees leaving a yellow fever epidemic in the Caribbean Islands sailed in, carrying the virus with them. Yellow fever causes yellowing of the skin, fever, and bloody vomiting. Five thousand people died, and 17,000 fled the city.

End: The vaccine was developed and then licensed in 1953. One vaccine is enough for life. It’s mostly recommended for those 9 months and older, especially if you live or travel to high-risk areas. You can find these specific countries at the Centers for Disease Control and Prevention (CDC) website.

Now: Mosquitoes are key to how this disease spreads, especially in countries like Central and South America and Africa. Eliminating them has been successful in controlling yellow fever. While yellow fever has no cure, someone who does recover from the illness becomes immune for the rest of their life.

1832-1866: Cholera in three waves

The United States had three serious waves of cholera, an infection of the intestine, between 1832 and 1866. The pandemic began in India, and swiftly spread across the globe through trade routes. New York City was usually the first city to feel the impact. An estimated two to six Americans died per day during the outbreak.

End: It’s unclear what ended the pandemics, but it may have been the change in climate or quarantines. The last documented outbreak in the United States was in 1911. Immediate cholera treatment is crucial, as it can cause death. Treatment includes antibiotics, zinc supplementation, and rehydration.

Now: Cholera still causes nearly 130,000 deaths a year worldwide, according to the CDC. Modern sewage and water treatment have helped eradicated cholera in some countries, but the virus is still present elsewhere.

You can get a vaccine for cholera if you’re planning to travel to areas that are high-risk. The best way to prevent cholera is to wash hands regularly with soap and water, and avoid drinking contaminated water.

1858: Scarlet fever also came in waves

Scarlet fever is a bacterial infection that can occur after strep throat. Like cholera, scarlet fever epidemics came in waves. During the 1858 epidemic, 95 percent of people who caught the virus were children.

End: Older studies argue that scarlet fever declined due to improved nutrition, but research shows that improvements in public health were more likely the cause.

Now: There is no vaccine to prevent strep throat or scarlet fever. It’s important for those with strep throat symptoms to seek treatment as quickly as possible. Your doctor will typically treat scarlet fever with antibiotics.

1906-1907: “Typhoid Mary”

One of the biggest typhoid fever epidemics of all time broke out between 1906 and 1907 in New York. Mary Mallon, often referred to as “Typhoid Mary,” spread the virus to about 122 New Yorkers during her time as a cook on an estate and in a hospital unit. About five of those 122 New Yorkers passed away from the virus. Annually, 10,771 people passed away from typhoid fever.

Medical testing showed that Mallon was a healthy carrier for typhoid fever. Typhoid fever causes sickness and red spots to form on the chest and abdomen.

End: A vaccine was developed in 1911, and an antibiotic treatment for typhoid fever became available in 1948.

Now: Today typhoid fever is rare. But it can spread through direct contact with infected people, as well as consumption of contaminated food or water.

1918: “Spanish flu”

This mutating influenza virus actually doesn’t come from Spain. It circulates the globe annually, but seriously affected the United States in 1918. The flu would return later in 1957 as the “Asian flu” and cause nearly 70,000 deaths before a vaccine became available.

End: After the end of World War I, cases of the flu slowly declined. None of the suggestions provided at the time, from wearing masks to drinking coal oil, were effective cures. Today’s treatments include bed rest, fluids, and antiviral medications.

Now: Influenza strains mutate every year, making last year’s vaccinations less effective.It’s important to get your yearly vaccination to decrease your risk for the flu.

1921-1925: Diphtheria epidemic

Diphtheria peaked in 1921, with 206,000 cases. Diphtheria causes swelling of the mucous membranes, including in your throat, that can obstruct breathing and swallowing. Sometimes a bacterial toxin can enter the bloodstream and cause fatal heart and nerve damage.

End: By the mid-1920s, researchers licensed a vaccine against the bacterial disease. Infection rates plummeted in the United States.

Now: Today more than 80 percent of children in the United States are vaccinated. Those who contract the disease are treated with antibiotics.

1916-1955: The peak of polio

Polio is a viral disease that affects the nervous system, causing paralysis. It spreads through direct contact with people who have the infection. The first major polio epidemic in the United States occurred in 1916 and reached its peak in 1952. Of the 57,628 reported cases, there were 3,145 deaths.

End: Three years later, Dr. Jonas Salk developed a vaccine. By 1962, the average number of cases dropped to 910. The CDC reports that the United States has been polio-free since 1979.

Now: Getting vaccinated is very important before traveling. There’s no cure for polio. Treatment involves increasing comfort levels and preventing complications.

1981-1991: Second measles outbreak

Measles is a virus that causes a fever, runny nose, cough, red eyes, and sore throat, and later a rash that spreads over the whole body. It’s a very contagious disease and can spread through the air. In the early 20th century, most cases involved children, due to inadequate vaccination coverage.

End: Doctors began to recommend a second vaccine for everyone. Since then, each year has had fewer than 1,000 cases.

Now: The United States experienced another outbreak of measles in 2014 and 2015. The CDC reports that this outbreak was identical to the measles outbreak in the Philippines in 2014. Be sure to get all the vaccinations your doctor recommends.

1993: Contaminated water in Milwaukee

One of Milwaukee’s two water treatment plants became contaminated with cryptosporidium, a parasitic disease that causes dehydration, fever, stomach cramps, and diarrhea. About 403,000 became ill, and more than 100 people died, making it the largest waterborne outbreak in United States history.

End: Most people recovered on their own. Of the people who passed, the majority had compromised immune systems.

Now: Improved water filtrations helped eradicate this disease, but an estimated 748,000 cases of cryptosporidium still occur each year. Cryptosporidium spreads through soil, food, water, or contact with infected feces. Be sure to practice personal hygiene, especially when camping.

2010, 2014: Whooping cough

Pertussis, known as whooping cough, is highly contagious and one of the most commonly occurring diseases in the United States. These coughing attacks can last for months. Infants too young for vaccination have the highest risk for life-threatening cases. Ten infants died during the first outbreak.

End: A whooping cough outbreak comes every three to five years. The CDC reports that an increase in the number of cases will likely be the “new normal.”

Now: The occurrence of the disease is much less than it was. The CDC recommends that pregnant women get a vaccination during the third trimester to optimize protection at birth.

1980s to present: The leading cause of early death

First documented in 1981, the epidemic we now know as HIV first appeared to be a rare lung infection. Now we know that HIV damages the body’s immune system and compromises its ability to fight off infections. AIDS is the final stage of HIV and the 6th leading cause of death in the United States among people 25 to 44 years old.

HIV may be transmitted sexually or through blood/body fluids from person to person. It can be transmitted from mother to unborn baby if not treated.

Now: While there is no cure for HIV, you can decrease your risk through safety measures like making sure your needles are sterilized and having protected sex. Safety measures can be taken during pregnancy to prevent the disease from being transmitted from an infected mother to child. For emergencies, PEP (post-exposure prophylaxis) is a new antiretroviral medicine that prevents HIV from developing within 72 hours.

Stay updated

Education

Educating yourself about current disease outbreaks can help you understand what precautions you should take in order to keep you and your family safe and healthy.

Take the time to search for ongoing epidemics by visiting the CDC’s Current Outbreak List, especially if you are traveling.

Protect yourself and your family

The good news is that the outbreaks listed here are rare and, in some cases, preventable. Make sure your family is up to date on their vaccinations before traveling, and get the latest flu vaccination. Simple steps in the kitchen and food safety techniques can also prevent you and your family from contracting or transferring infections.